Field of the Disclosure
[0001] This disclosure is directed to the field of pressure relief vents. More particularly,
the disclosure relates to pressure relief vents designed to open during an explosion
or in response to a pre-determined pressure differential to reduce damage.
Priority Claim
Background of the Disclosure
[0003] Many commercial and industrial processes create the possibility for explosions, even
the warehousing of combustible dusts and products that release combustible vapors
presents such a risk. Such explosions may damage or destroy any structure that is
not designed to resist the considerable pressures generated by a dust or vapor explosion.
Deflagration vents, blow out panels, explosion panels, or explosion vents have been
employed to lessen any damage to a structure housing potentially dangerous processes
when an explosive event occurs by allowing the pressure created in such an explosion
to escape through deflagration vents to mitigate and even prevent the deformation
and/or destruction of the structure. A pressure relief device is a broad term encompassing
at least all the venting devices described above. The above described venting practices
are particularly effective in the case of explosions that propagate below the speed
of sound, a deflagration. Industry standards such as NFPA 68 in the United States
and the ATEX directive, used in Europe, and related harmonized standards in Europe
and elsewhere establish requirements for such protective measures.
[0004] Because a temperature, climate, and/or clean controlled environment is desired, and
even required by some processes, deflagration vents have been employed that maintain
the environmental integrity of the structure. Such vents in the past have been held
in place by magnets, spring mechanisms, re-settable latches, or have been constructed
of frangible materials. One type of vent involves a burst panel, such as disclosed
in co-owned
U.S. Patent No. 7,950,408 ("the '408 patent"), the entire contents of which are incorporated herein by reference.
A burst panel may include a release mechanism configured to hold a panel member against
a frame, or may be sealed against a frame in some other fashion.
[0005] In an explosion or other event causing a vent to open, it may be desirable to prevent
the opened portion of the vent (e.g., the panel in a burst panel vent) from becoming
a projectile or otherwise falling and causing damage to persons or property. As disclosed
in the '408 patent, the opened portion of the vent may be attached to the structure,
or to a vent frame installed in the structure, by a shock cord or cable. Alternatively
in the '408 patent, the opened portion of the vent may be attached to the structure
or vent frame by way of a hinge or other attachment mechanism.
[0006] In the known applications of vents, including burst panel vents, retaining an opened
portion of the vent attached to the structure or vent frame may transfer relatively
high forces to the structure as the opened portion of the vent opens. For example,
a known burst panel vent is typically used with a high-strength enclosure that can
survive a "reduced explosion pressure" (P
red)-i.e., the maximum pressure developed in a vented enclosure during a vented deflagration-of
1½ pounds per square inch gage (psig) or more. Such enclosures typically are constructed
from reinforced concrete, bolted or welded steel fabrications, and fiber reinforced
fabrications or a combination of materials to achieve the necessary operating strength.
Even though the activation pressure (P
stat) of a vent used in such an enclosure may be lower than 1½ psig-typically 1/3 psig
or less for large volume building structures-the pressure generated by a deflagration
will continue to increase after the vent has opened due to the dynamic nature of a
deflagration and/or combustion event; therefore, the strength of the enclosure elements
that retain the vent must be sufficiently strong to survive an explosion using a known
explosion vent. The force that must be carried by the enclosure at the vent location
can be determined from the value of P
red and the vent area. For example, a vent might have a nominal size of 36-inches x 36-inches,
presenting a vent area of 1296 square inches. At a set pressure of 1/3 psig this could
impart a load of 432 pounds on the vent-retaining element of the enclosure. However,
the enclosure and/or vent-retaining element may be required to survive a P
red of 1½ psig-which could impart a force of 1944 pounds. In other applications, a P
red of 3psig would impart a force of 3888 pounds. These are forces that can lead to failure
of enclosure vent mounting arrangements. In a worst case scenario, a vent-mounting
frame arrangement could be torn out of the enclosure under such high forces, presenting
a secondary mechanical hazard.
[0007] It is desirable to enable safe venting of lower strength enclosures, such as sheet
metal or simple masonry, which may not survive the P
red of the vent application. It also is desirable to enable venting where the mounting
arrangement of a vent (e.g., the frame, bolts, and/or other mechanism(s) by which
a vent is installed in a structure or enclosure) cannot otherwise cope with the momentary
forces generated when a known vent activates in response to a deflagration. The forces
generated on a mounting arrangement are a function of vent area and P
red. Thus, with large vent areas occupying several square feet, the combined loading
of even a fraction of a psi of pressure can be considerable. Accordingly, it is desirable
to provide a vent that will reduce the forces imparted on a mounting arrangement and/or
enclosure when a large vent area opens in response to a deflagration. The present
disclosure provides one or more of these, and/or other, advantages.
Summary
[0009] Several of the following embodiments and drawings only serve as examples of generic
pressure relief devices. The invention is defined by the appended claims. In one embodiment,
a pressure relief device comprises a first vent comprising a first panel, a second
vent comprising a second panel, and a connecting member interposed between the first
panel and second panel. The first panel and second panel are configured to rotate
relative to the connecting member. The first panel is configured to open upon activation
of the first vent, and the second panel is configured to open upon activation of the
second vent. The first panel and second panel are configured to engage at least their
outer ends upon opening.
[0010] In another embodiment, a pressure relief device comprises a frame having a central
portion. A first burst panel is mounted within the frame, wherein the first burst
panel is configured to rotate relative to the central portion upon opening. A second
burst panel is mounted within the frame, wherein the second burst panel is configured
to rotate relative to the central portion upon opening. The first burst panel and
second burst panel are configured to activate and open upon experiencing a predetermined
pressure differential. And at least a portion of the first burst panel engages with
at least a portion of the second burst panel upon activation.
[0011] In still another embodiment, a pressure relief device comprises a sheet. The sheet
includes a first line of weakness defining a first burst panel, a second line of weakness
defining a second burst panel, and a central portion between the first burst panel
and the second burst panel. The first burst panel is configured to activate and rotate
relative to the central portion upon experiencing a predetermined pressure differential,
wherein rotation of the first burst panel creates a first opening in the sheet. The
second burst panel is configured to activate and rotate relative to the central portion
upon experiencing a predetermined pressure differential, wherein rotation of the second
burst panel creates a second opening in the sheet. And at least a portion of the first
burst panel is configured to contact at least a portion of the second burst panel
upon activation of the first burst panel and second burst panel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The accompanying drawings, which are incorporated in and constitute a part of this
specification, illustrate several embodiments of the disclosure and together with
the description, serve to explain the principles of the disclosure.
FIG. 1A is a view of a pressure relief device in the form of a butterfly vent, according
to one embodiment of the present disclosure.
FIG. 1B illustrates the butterfly vent of FIG. 1A after activation or opening.
FIG. 2 illustrates an embodiment of a pressure relief device in the form of a butterfly
vent, which a connecting member formed integrally with two partially cut-out blow-out
panels.
FIGS. 3A-3B illustrate an embodiment of the disclosure including two side-by-side
vents arranged to open in a butterfly vent configuration.
FIGS. 4A-4C illustrate different views of an embodiment of a butterfly vent including
domed blow-out panels.
FIGS. 5A-5B illustrate different views of an embodiment of a butterfly vent with a
cord connecting two burst panels.
FIGS. 6A-6E illustrate different views of an embodiment of a butterfly vent with a
release mechanism and a cord connecting two burst panels.
FIG. 7 illustrates a cross-sectional view of an embodiment of a butterfly vent with
a release mechanism and domed burst panels.
FIG. 8 illustrates a hinge that may be used with a butterfly vent.
FIG. 9 illustrates another embodiment of a hinge that may be used with a butterfly
vent.
FIG. 10 illustrates a butterfly vent configured with a pair of hinges.
FIG. 11 illustrates an embodiment of a release mechanism that may be used with a butterfly
vent.
FIG. 12 illustrates an embodiment of a braking member that may be used with a butterfly
vent.
FIG. 13 illustrates an embodiment of a butterfly vent including circular-shaped burst
panels.
FIG. 14 illustrates an embodiment of a butterfly vent including semi-circular-shaped
burst panels.
DESCRIPTION OF THE EMBODIMENTS
[0013] Reference will now be made in detail to the present exemplary embodiments of the
disclosure, examples of which are illustrated in the accompanying drawings. Wherever
possible, the same reference numbers will be used throughout the drawings to refer
to the same or like parts.
[0014] For the purposes of this disclosure, an explosive event may include any event causing
the pressure relief vent to open. Such events may include a dust or gas explosion,
any event that causes pressure to build rapidly inside of a structure, a weather event
causing a sufficient pressure differential, a physical blow to the vent causing it
to open, an HVAC error causing a sufficient pressure differential, other accidental
openings, etc.
[0015] FIG. 1A illustrates an exemplary butterfly vent consistent with the present disclosure.
The butterfly vent may comprise, for example, a vent 10. The vent 10 may include a
pair of blow-out portions 11 and 12 held into a frame 13. The frame 13 may be installed
in a structure or other enclosure 20. In FIG. 1A, the frame 13 is installed in the
structure or enclosure 20 by a series of bolts 15.
[0016] As illustrated in FIG. 1A, a connecting member 14 may extend between the pair of
blow-out portions 11 and 12. The blow-out portions 11 and 12 may be configured to
open or "blow out" in response to an increased pressure within the structure or enclosure.
In the embodiment of FIG. 1A, the blow-out portions 11 and 12 are arranged in a "butterfly
vent" configuration, such that they are configured to open in a manner similar to
a butterfly flapping its wings. More specifically, the blow-out portions of FIG. 1A
are configured to rotate around the connecting member 14 and clap together upon opening,
as illustrated in FIG. 1B.
[0017] FIG. 1B illustrates the butterfly vent of FIG. 1A in an open condition. As shown
in FIG. 1B, the paired blow-out portions 11 and 12 swing outward and clap together
upon opening. The impact between the paired blow-out portions 11 and 12 absorbs kinetic
energy (which may be dissipated, e.g., in the form of sound, heat, deformation, vibration
of the blow-out portions 11 and 12). In one embodiment, the paired blow-out portions
11 and 12 may be configured to join together upon impact. Newton's Third Law of Physics
teaches that every action has an equal and opposite reaction. Thus, when the two blow-out
portions collide-each having the same nominal size and mass and being driven by the
same force-the energy is cancelled without imparting stress into the supporting vent
frame and enclosure structure. As a result, less kinetic energy remains to be absorbed
by the frame 13 and, by extension, the structure or enclosure 20. In this manner,
the butterfly vent provides advantages over known vents, including known burst panel
vents. The frame 13, or the structure/enclosure 20 in which the frame is installed,
may be made of a weaker material (or using less material) than if a butterfly vent
is not used, thereby saving cost and complexity of manufacture. Because the butterfly
vent of the present disclosure reduces kinetic loads on a structure or enclosure,
the butterfly vent may be used with relatively weak structures (e.g., sheet metal
structures) on which known burst panels and other vents may not be suitable. In addition,
the number and size of bolts or other attachment mechanisms used to install a frame
within a structure/enclosure also may be reduced when a butterfly vent is used.
[0018] In the embodiment of FIGS. 1A and 1B, connecting member 14 is illustrated as a component
separate from blow-out panels 11 and 12. For example, connecting member 14 may be
a portion of the frame 13, or may be a component attached to the frame 13.
[0019] In another embodiment, illustrated in FIG. 2, connecting member 214 may be integrally
formed with one or more of burst panels 211 and 212. For example, connecting member
214 and burst panels 211 and 212 may be formed from a single sheet of material. As
illustrated in FIG. 2, burst panel 211 is partially defined by a line of weakness
242, which may be (for example) a cut, etched, or stamped perimeter, and which extends
around three sides of a rectangular burst panel profile. A fourth side of the rectangular
burst panel profile, indicated by dotted line 241, may be a line of bending. Similarly
in FIG. 2, burst panel 212 is partially defined by a line of weakness 244, which may
be (for example) a cut, etched, or stamped perimeter, and which extends around three
sides of a rectangular burst panel profile. A fourth side of the rectangular burst
panel profile, indicated by dotted line 243, may be a line of bending. The lines of
bending 241 and 243 may be defined by a line of weakness created by, e.g., a cut,
partial cut, etch, stamp, or perforation in the sheet of material. Alternatively,
the line of bending 241, 243 may be uncut or unweakened. In one embodiment, a hinge
element may be provided along a line of bending to facilitate bending and/or retention
of a burst panel upon bursting.
[0020] A connecting member 214 is formed between the lines of bending 241 and 243. In response
to an explosive event within enclosure 220, burst panels 211 and 212 may tear open
along cut or etched perimeters 242 and 244, bending toward each other along lines
of bending 241 and 243 (similarly to FIG. 1B). In one embodiment, connecting member
214 may be reinforced.
[0021] As illustrated in FIG. 2, the butterfly vent is applied directly to the enclosure
220 without the use of a separate "frame." It is contemplated that a butterfly vent
may be installed with an enclosure using, e.g., stud bolts, welding, clamps, adhesives,
or other attachment mechanisms without an outlet frame.
[0022] FIGS. 3A-3B illustrate an embodiment including two separate vents 310 and 320 installed
adjacent to one another. The vents may be arranged to open in a butterfly vent configuration
according to the present disclosure, so that panels 311 and 321 rotate toward each
other when opened, as illustrated in FIG. 3B.
[0023] FIGS. 4A-4C illustrate another embodiment of a butterfly vent 410. As illustrated
in FIG. 4A, a connecting member 414 may extend between a pair of blow-out portions
411 and 412 arranged in a "butterfly vent" configuration. More specifically, the blow-out
portions of FIG. 4A are configured to rotate around the connecting member 414 upon
opening, as illustrated in FIG. 4C. As best illustrated in FIG. 4B, which is a view
of the vent along line A-A as designated in FIG. 4A, the blow-out portions 411 and
412 may be provided with a domed or bulged configuration. In this manner, when the
blow-out portions 411 and 412 clap together upon opening (i.e., as shown in FIG. 4C),
the blow-out portions 411 and 412 may crumple or otherwise deform, thereby absorbing
kinetic energy from the vent's opening. When blow-out portions 411 and 412 "clap together,"
at least a portion of blow-out portion 411 contacts at least a portion of blow-out
portion 412. In one embodiment, an outer edge of blow-out portion 411 contacts an
outer edge of blow-out portion 412. By clapping together, the butterfly vent 410 may
further reduce the amount of force transferred to the frame 413 or enclosure (not
shown in FIGS. 4A-4C).
[0024] FIGS. 5A and 5B illustrate another embodiment of a butterfly vent 510. A butterfly
vent may include a frame 513, in which two burst panels 511 and 512 are sealed. Burst
panels 511 and 512 may be sealed to the frame 513, adjacent to each other, on opposite
sides of connecting member 514. The frame 513 may be arranged such that an outer flange
533 is created around the periphery of the vent 510 allowing installation into a conventional
window opening in a building or other commercial or residential structure or other
enclosure. The outer flange 533 may include one or more bolt holes 550 (FIG. 5A).
As illustrated in FIG. 5B, the burst panels 511 and 512 may be secured to the frame
via their central hubs (comprising bolts 522, 524, and washers 521, 523, 525, and
527, as described below). Additionally or alternatively, the frame 513 may be provided
with one or more dowels 531 or other components to house or secure burst panels 511
and 512 within the frame 513.
[0025] As illustrated in FIGS. 5A and 5B, a cord 526 connects burst panels 511 and 512 to
each other. As illustrated in FIGS. 5A and 5B, cord 526 is attached at either end
to bolt 522 in burst panel 511 and bolt 524 in burst panel 512. The cord 526 may be
installed in tension between bolts 522 and 524, which may contribute to the sealing
of burst panels 511 and 512 to the frame 513. An inlet-side washer (521, 523) and
outlet-side washer (525, 527) may be used to distribute forces imparted by the bolts
(522, 524) on the burst panels (511, 512). In one embodiment, the cord 526 may pass
through a hole or eyelet provided within or attached to connecting member 514.
[0026] The burst panels 511 and 512 are configured to open upon experiencing a predetermined
pressure differential, resulting in separation of panels 511 and 512 from frame 513,
thereby safely venting the pressure differential through the openings left within
the frame 513. The cord 526 retains the burst panels 511 and 512 to the frame 513
upon opening. The cord 526 also ensures that the burst panels 511 and 512 open in
a butterfly vent fashion-i.e., burst panels 511 and 512 rotate around connecting member
514 and clap together.
[0027] In one embodiment, cord 526 tunes the timing of opening of the burst panels-i.e.,
cord 526 ensures that burst panels 511 and 512 open in a coordinated manner. Due to
the age of a seal, manufacturing tolerances, improper installation, etc., one burst
panel 511 may open prior to the other burst panel 512 in response to a pressure differential.
It may be preferred, however, that both burst panels 511 and 512 open approximately
simultaneously. Simultaneous opening of burst panels 511 and 512 may maximize the
vent area open at the onset of an explosive event (which may increase safety and efficiency)
and also may ensure that the energy-absorbing benefits of a butterfly vent configuration
(i.e., when the paired burst panels 511 and 512 clap against each other) are achieved.
In the illustrated embodiment, when burst panel 511 opens, it pulls on burst panel
512 via cord 526. That tension-directed perpendicularly to the direction of burst
panel release-may free burst panel 512 from its seal (or other retention device),
allowing burst panel 512 to open approximately simultaneously with burst panel 511.
[0028] In another embodiment, as illustrated in FIGS. 6A-6E, a butterfly vent may be provided
with a release mechanism, such as are disclosed in the '408 patent. As illustrated
in FIG. 6A, a butterfly vent 610 may include a first panel member 611 and a second
panel member 612, such as a polycarbonate window, held into a frame 613, such as an
aluminum frame, with a release mechanism 616. A connecting member 614 may be positioned
between the two panel members.
[0029] FIG. 6B depicts a perspective view of an inlet side of vent 610, which is illustrated
as being located within a frame 613. As seen in FIG. 6B, the panel members 611 and
612 are installed such that they are positioned on the outlet side (i.e., facing away
from the enclosure) relative to the frame 613.
[0030] The frame 613 may also have one or more cross members 680 (FIG. 6B) to provide stability
and anchor points for release mechanisms 616. The release mechanisms may be, for example,
a release mechanism as described in the '408 patent. In one embodiment, the release
mechanisms 616 may be a release mechanism as illustrated in FIG. 4 of the '408 patent.
When a predetermined pressure differential exists between the inlet side and the outlet
side of the panel members 611 and 612 (e.g., when an explosive event occurs within
the enclosure), the panel members 611 and 612 are forced away from the frame 613,
toward the outlet direction. The force load applied to the panel members 611 and 612
transfer a force to the release mechanisms 616, resulting in separation of the panel
members 611 and 612 from frame 613 and the cross member 680, thereby safely venting
the pressure differential through the opening left within the frame 613.
[0031] As seen in FIG. 6B, the cross member 680 may provide a convenient location for mounting
the release mechanisms 616. A washer member 621, 622 may contact the inlet side of
the panel members 611 and 612 and be located on the release mechanism 616 between
the panel members 611 and 612 and cross member 680. In addition, the cross member
680 may provide enhanced resistance to accidental physical contact along the inlet
side of panel members 611 and 612, resistance to vacuum pressures, or resistance to
strong wind loading on the panel members 611 and 612.
[0032] FIG. 6C depicts a perspective view of an outlet side of vent 610, which is illustrated
as being located within a frame 613. As seen in FIG. 6B, in one embodiment, washer
members 625, 627 are located on the outlet side of the panel members 611 and 612 and
receive the release mechanisms 616. The washer members 625, 627 serve to distribute
force over a larger area of panel members 611 and 612 upon occurrence of a predetermined
pressure differential. For example, the washer members 625, 627 may be configured
to distribute the load of an explosive event across sufficient surface area of the
panel member to minimize the possibility of the panel breaking around or pulling off
the release mechanisms 616.
[0033] FIG. 6D illustrates a cross-sectional view of the vent system 610 taken through a
cross-member 680 of the vent system 610 when the vent system 610 is in an installed,
pre-venting configuration. As seen in FIG. 6D, the panel members 611 and 612 may be
sealed against the aluminum frame 613 with gaskets or weather stripping 690. The gasket
or weather stripping 690 allows the vent system 610 to be weather-tight. The gasket
or weather stripping 690 may also allow for expansion of the panel members 611 and
612 as a result of heat, while still allowing sufficient clearance for the panel members
611 and 612 to release from the frame 613 if an explosive event occurs.
[0034] As seen in FIG. 6D, the panel members 611 and 612 may be held against the frame 613
with release mechanisms 616. The release mechanisms 616 may pass through apertures
in the panel members, as well as through apertures through the cross member 680 to
hold the panel members tight against the frame 613.
[0035] As FIG. 6D illustrates, frame 613 may be made of "T" stock, e.g., aluminum "T" stock.
The "T" stock may be arranged such that an outer flange 533 is created around the
periphery of the vent 610 allowing installation into a conventional window opening
in a building or other commercial or residential structure or other enclosure. The
outer flange 633 may include one or more bolt holes (not shown). The "T" stock arrangement
may also provide an inner flange 635 on the inside of the frame 613 to house the burst
panels 611 and 612.
[0036] In the exemplary embodiment depicted in FIGS. 6A-6E, the release mechanisms 616 include
a failure member 617 comprised of an element configured to break upon the application
of a predetermined force. Accordingly, when a predetermined pressure differential
occurs, the panel members 611 and 612 exert a predetermined force on the failure members
617 resulting in a break along the failure members 617 and allowing separation of
the panel members 611 and 612 from frame 613 and the cross member 680 (as illustrated
in FIG. 6E), thereby safely venting the pressure differential through the opening
left within the frame 613. The failure member may be a failure member such as is disclosed
in the '408 patent.
[0037] As shown in FIGS. 6D-6E, the panel members 611 and 612 may be further attached to
each other by a cord 626 or cable. In one embodiment, the cord 626 may also be attached
to the frame 613 to prevent the panel members 611, 612 from becoming projectiles or
otherwise falling and causing damage to persons or property. The cord 626 or cable
also ensures that the burst panels 611 and 612 open in a butterfly vent fashion-i.e.,
burst panels 611 and 612 rotate around connecting member 614 and clap together. In
one embodiment, cord 626 also ensures that burst panels 611 and 612 open in a coordinated
manner.
[0038] The cord 626 or cable may be attached to the panel members 611, 612 through the release
mechanisms 616 or to other points on the panel members. The cord 626 or cable may
be attached to the cross member 680 (or another location on the structure of frame
613). In one embodiment, a braking member may be used with the cord. Where the cord
626 or cable is constructed of a material having elastic properties, some of the force
from the panel members 611 and 612 leaving the frame 613 may be absorbed without the
cord 626 breaking, snapping, fraying, or otherwise failing.
[0039] An exemplary braking member 1250 is illustrated in FIG. 12. The braking member 1250
may be configured such that it bends as a cord (e.g., 626) pulls against it. In this
manner, the braking member 1250 can absorb some of the kinetic energy force upon the
opening of a panel. In one embodiment, the braking member 1250 may comprise a material
with relatively high elongation properties and may elongate to absorb kinetic energy.
In addition, or as an alternative, the shape of the braking member may be modified
to facilitate the absorption of kinetic energy. For example, as illustrated in FIG.
12, a braking member may have a first end 1260 with an aperture 1262 to facilitate
connection of the braking member 1250 to a frame or other structure. The braking member
may have a second end 1264 with an aperture 1266 to facilitate connection to a cord
(e.g., 626). The braking member 1250 may exhibit a wavy shape (e.g., a sinusoidal
shape), such that as the braking member is pulled tight by a cord after the release
of a panel, the pattern of waves transition to a relatively more straightened pattern
as kinetic energy is absorbed.
[0040] FIG. 7 is a cross-sectional view of another embodiment of a butterfly vent. As seen
in FIG. 7, the panel members 711, 712 may be domed or bulged. The panel members 711
and 712 may be held against a frame 713 by way of release mechanisms 716. When a predetermined
pressure differential is reached, the release mechanisms 716 may release the panel
members 711, 712. A cord 726 ensures that the panel members 711, 712 open in a butterfly
vent fashion. That is, the panel members will rotate around a connecting member 714
and clap together. The panel members 711, 712 may deform upon contacting each other,
thereby absorbing kinetic energy.
[0041] FIGS. 8-10 depict various hinges 81, 91, 101 that may be used with a butterfly vent.
A hinge 81, 91, 101 may be used to ensure that paired vents open in a butterfly vent
configuration (
see, e.g., FIG. 10), with their flaps rotating toward each other around a central connecting
member. A hinge also may be used to absorb further kinetic energy upon activation
of a butterfly vent system. Exemplary hinges are disclosed in the '408 patent. A hinge
may be provided with a stress distribution feature, such as are described in commonly-owned
U.S. Patent No. 6,792,964 B2, the entire contents of which are hereby incorporated by reference. Alternatively,
a hinge may be provided by integrally connecting the panel member to one side of the
frame, similar to explosion panel embodiments described in
U.S. Patent No. 6,792,964 B2.
[0042] It is contemplated that any number of release mechanisms may be used with the disclosed
butterfly vent. For example, each of a pair of vent panels in a butterfly vent may
include a release mechanism such as are illustrated in FIGS. 10 and 11 of the '408
patent. Such an embodiment is illustrated in FIGS. 6D (pre-activation) and 6E (post-activation)
of the present disclosure.
[0043] One embodiment of a release mechanism 1116 is illustrated in FIG. 11. As illustrated,
release mechanism 1116 may pass through an aperture in the panel member (e.g., 611,
as illustrated in FIG. 6A), as well as through an aperture in the cross member (e.g.,
680, as illustrated in FIG. 6B) to hold a panel member tight against a frame. With
reference to FIG. 11, in one embodiment, the release mechanism 1116 comprises a shaft
1130 having a first end terminating in a flanged head 1131 and a second end terminating
in a connector 1133 having an aperture 1135 therethrough. A failure member 1132 is
located between connector 1133 and the flanged head 1131. The release mechanism 1116
also may include a collar 1134 and pin 1136. The failure member 1132 may include a
weakened section 1144, whereby the failure member 1132 is configured to break upon
the application of a predetermined tensile force on the failure member 1132. In one
embodiment, the failure member 1132 may take the form of a flat plate, and the weakened
section 1144 may comprise a portion of the flat plate having reduced thickness or
width. The failure member 1132 may be designed to control the pressure differential
at which a panel member will open.
[0044] Although FIG. 11 illustrates on embodiment of a release mechanism, any suitable release
mechanism may be used, including the release mechanisms illustrated in FIGS. 10 and
11 of the '408 patent.
[0045] Although the disclosed butterfly vents are generally disclosed as rectangular in
shape, it is contemplated that any number of vent shapes may be used. For example,
a butterfly vent may include a pair of circular or semi-circular blowout panels, as
illustrated, for example, in FIGS. 13 and 14.
[0046] As illustrated in FIG. 13, circular burst panels 1311 and 1312 may be formed from
a single sheet. As shown, burst panel 1311 is partially defined by a line of weakness
1342, which extends around an arc of a circular burst panel profile. A portion of
the burst panel profile, indicated by dotted line 1341, may be a line of bending.
Similarly in FIG. 13, burst panel 1312 is partially defined by a line of weakness
1344, which extends around an arc of a circular burst panel profile. A portion of
the circular burst panel profile, indicated by dotted line 1343, may be a line of
bending. A connecting member 1314 is formed between the lines of bending 1341 and
1343. The lines of weakness 1342, 1344 may be formed, for example, through cutting,
partially cutting, indenting, stamping, or perforating the sheet material comprising
the burst panels. The lines of bending 1341, 1343 may be weakened or unweakened. In
one embodiment, a hinge element may be provided with a line of bending. In response
to an explosive event within an enclosure (not illustrated), burst panels 1311 and
1312 may tear open along cut or etched perimeters 1342 and 1344, bending toward each
other along lines of bending 1341 and 1343 (similarly to the embodiment illustrated
in FIG. 1B).
[0047] Also as illustrated in FIG. 14, semi-circular burst panels 1411 and 1412 may be formed
from a single sheet. As illustrated, burst panel 1411 is partially defined by a line
of weakness 1442, which extends around an arc of a semi-circular burst panel profile.
A portion of the burst panel profile, indicated by dotted line 1441, may be an uncut
or partially uncut line of bending. Similarly in FIG. 14, burst panel 1412 is partially
defined by a cut or etched perimeter 1444, which extends around three sides of a rectangular
burst panel profile. A fourth side of the rectangular burst panel profile, indicated
by dotted line 1443, may be an uncut or partially uncut line of bending. A connecting
member 1414 is formed between the lines of bending 1441 and 1443. The lines of weakness
1442, 1444 may be formed, for example, through cutting, partially cutting, indenting,
stamping, or perforating the sheet material comprising the burst panels. The lines
of bending 1441, 1443 may be weakened or unweakened. In one embodiment, a hinge element
may be provided with a line of bending. In response to an explosive event within an
enclosure (not illustrated), burst panels 1411 and 1412 may tear open along cut or
etched perimeters 1442 and 1444, bending toward each other along lines of bending
1441 and 1443 (similarly to the embodiment illustrated in FIG. 1B).
[0048] !n addition to rectangular, circular, and semi-circular burst panels, it is contemplated
that a burst panel in a butterfly vent may be any suitable shape. For example, a burst
panel may be oval-shaped, triangular-shaped, or irregularly shaped.
[0049] The previously discussed embodiments are disclosed as exemplary only and not as limiting
the scope of the disclosure to the particular embodiments. Every embodiment disclosed
above is not intended to be exclusive or stand alone. For example, it is contemplated
that the particular features in any one embodiment can be substituted for, or replaced
with, the features of any other embodiment (even though such a particular embodiment
may not be explicitly disclosed. In addition, it is contemplated that multiple burst
panels may be combined in a single apparatus. For example, a butterfly vent may include
multiple pairs of blowout panels mounted in an array.
[0050] Other embodiments of the disclosure will be apparent to those skilled in the art
from consideration of the specification and practice of the disclosure herein. It
is intended that the specification and examples be considered as exemplary only.
1. A pressure relief device, comprising:
a frame having a central portion;
a first burst panel (511) mounted within the frame, wherein the first burst panel
(511) is configured to rotate relative to the central portion upon opening; and
a second burst panel (512) mounted within the frame, wherein the second burst panel
(512) is configured to rotate relative to the central portion upon opening;
wherein the first burst panel (511) and second burst panel (512) are configured to
activate and open upon experiencing a predetermined pressure differential; and
wherein at least a portion of the first burst panel (511) engages with at least a
portion of the second burst panel (512) upon activation.
2. The pressure relief device of claim 1, wherein the central portion of the frame defines
an eyelet; the device further comprising:
a cord (526) having a first end and a second end;
wherein the cord (526) is passed through the eyelet;
wherein the first end of the cord (526) is attached to the first panel (511); and
wherein the second end of the cord (526) is attached to the second panel (512).
3. The pressure relief device of claim 2, wherein the cord (526) is configured to ensure
that the first burst panel (511) and second burst panel (512) activate at substantially
the same time.
4. The pressure relief device of claim 2, further comprising:
a first hinge, wherein the first hinge joins the first burst panel (511) to the central
portion of the frame; and
a second hinge, wherein the second hinge joins the second burst panel (512) to the
central portion of the frame.
5. A pressure relief device according to claim 1, comprising:
a sheet;
wherein the sheet includes a first line of weakness (242) defining the first burst
panel (211), a second line of weakness (244) defining the second burst panel (212);
wherein rotation of the first burst panel (211) creates a first opening in the sheet;
and
wherein rotation of the second burst panel (212) creates a second opening in the sheet;
and
wherein at least a portion of the first burst panel is configured to contact at least
a portion of the second burst panel upon activation of the first burst panel and second
burst panel.
6. The pressure relief device of claim 5:
wherein the first burst panel (211) has four sides, wherein the first line of weakness
(242) is a cut defining three sides of the first burst panel (211), and wherein the
fourth side of the first burst panel (211) is a first line of bending (241) joining
the first burst panel (211) to the central portion; and
wherein the second burst panel (212) has four sides, wherein the second line of weakness
(244) is a cut defining three sides of the second burst panel (212), and wherein the
fourth side of the second burst panel (212) is a second line of bending (243) joining
the second burst panel (212) to the central portion.
7. The pressure relief device of claim 6, wherein the first line of bending (241) is
defined by a partial cut, and wherein the second line of bending (243) is defined
by a partial cut.
8. The pressure relief device of claim 5:
wherein the first line of weakness (242) is an arc-shaped cut, and wherein a first
line of bending (241) joins the first burst panel to the central portion; and
wherein the second line of weakness (244) is an arc-shaped cut, and wherein a second
line of bending (243) joins the second burst panel to the central portion.
9. The pressure relief device of claim 5, further comprising:
a first hinge member engaged between the first burst panel (211) and the central portion;
and
a second hinge member engaged between the second burst panel (212) and the central
portion.
10. The pressure relief device of claim 5, further comprising:
a cord (526) joining the first burst panel (511) to the second burst panel (512);
wherein the cord (526) is configured to transmit a tensile force between the first
burst panel (511) and second burst panel (512) upon activation of the first burst
panel (511).
11. A pressure relief device according to claim 1, comprising:
a first vent, the first vent comprising the first panel (511);
a second vent, the second vent comprising the second panel (512);
wherein the first panel (511) and the second panel (512) are optionally domed; and
a connecting member (514) interposed between the first panel (511) and second panel
(512), the first panel (511) and second panel (512) configured to rotate relative
to the connecting member (514);
wherein the first panel (511) is configured to open upon activation of the first vent;
wherein the second panel (512) is configured to open upon activation of the second
vent; and
wherein the first panel (511) and second panel (512) are configured to engage at least
their outer ends upon opening.
12. The pressure relief device of claim 11, further comprising:
a cord (526) having a first end and a second end, the first end joined to the first
panel (511) and the second end joined to the second panel (512), optionally at least
one braking member being attached to the cord (526); and
optionally wherein the cord (526) is configured to join the first panel (511) and
second panel (512) in tension.
13. The pressure relief device of claim 12, wherein upon activation of the first vent,
the first panel (511) is configured to pull on the cord (526) and thereby trigger
activation of the second vent;
optionally wherein the cord (526) causes the first vent and second vent to activate
substantially simultaneously.
14. The pressure relief device of claim 11, further comprising:
a first activation mechanism configured to control a pressure at which the first vent
activates; and
a second activation mechanism configured to control a pressure at which the second
vent activates.
15. The pressure relief device of claim 11, further comprising:
a first hinge rotatably joining the first panel (511) to the connecting member (514);
and
a second hinge rotatably joining the second panel (512) to the connecting member (514);
wherein the first hinge and the second hinge are optionally configured to deform and
thereby absorb kinetic energy upon activation of the first vent and second vent.
1. Druckentlastungsvorrichtung, umfassend:
einen Rahmen mit einem zentralen Teil;
eine erste Berstscheibe (511), die in dem Rahmen angebracht ist, wobei die erste Berstscheibe
(511) so gestaltet ist, dass sie sich beim Öffnen im Verhältnis zu dem zentralen Teil
dreht; und
eine zweite Berstscheibe (512), die in dem Rahmen angebracht ist, wobei die zweite
Berstscheibe (512) so gestaltet ist, dass sie sich beim Öffnen im Verhältnis zu dem
zentralen Teil dreht;
wobei die erste Berstscheibe (511) und die zweite Berstscheibe (512) so gestaltet
sind, dass sie aktiviert werden und sich öffnen, wenn ein vorbestimmter Druckunterschied
eintritt; und
wobei bei Aktivierung wenigstens ein Teil der ersten Berstscheibe (511) mit wenigstens
einem Teil der zweiten Berstscheibe (512) eingreift.
2. Druckentlastungsvorrichtung nach Anspruch 1, wobei der zentrale Teil des Rahmens eine
Öse definiert, wobei die Vorrichtung ferner folgendes umfasst:
ein Kabel (526) mit einem ersten Ende und einem zweiten Ende;
wobei das Kabel (526) durch die Öse geführt wird;
wobei das erste Ende des Kabels (526) an der ersten Scheibe (511) angebracht ist;
und
wobei das zweite Ende des Kabels (526) an der zweiten Scheibe (512) angebracht ist.
3. Druckentlastungsvorrichtung nach Anspruch 2, wobei das Kabel (526) so gestaltet ist,
dass es sicherstellt, dass die erste Berstscheibe (511) und die zweite Berstscheibe
(512) im Wesentlichen gleichzeitig aktiviert werden.
4. Druckentlastungsvorrichtung nach Anspruch 2, wobei diese ferner folgendes umfasst:
ein erstes Gelenk, wobei das erste Gelenk die erste Berstscheibe (511) mit dem zentralen
Teil des Rahmens verbindet; und
ein zweites Gelenk, wobei das zweite Gelenk die zweite Berstscheibe (512) mit dem
zentralen Teil des Rahmens verbindet.
5. Druckentlastungsvorrichtung nach Anspruch 1, umfassend:
eine Platte;
wobei die Platte eine erste Sollbruchlinie (242) aufweist, welche die erste Berstscheibe
(211) definiert, und eine zweite Sollbruchlinie (244), welche die zweite Berstscheibe
(212) definiert;
wobei eine Rotation der ersten Berstscheibe (211) eine erste Öffnung in der Platte
erzeugt; und
wobei eine Rotation der zweiten Berstscheibe (212) eine zweite Öffnung in der Platte
erzeugt; und
wobei wenigstens ein Teil der Berstscheibe so gestaltet ist, dass er bei Aktivierung
der ersten Berstscheibe und der zweiten Berstscheibe wenigstens einen Teil der zweiten
Berstscheibe berührt.
6. Druckentlastungsvorrichtung nach Anspruch 5,
wobei die erste Berstscheibe (211) vier Seiten hat, wobei die erste Sollbruchlinie
(242) ein Schnitt ist, der drei Seiten der ersten Berstscheibe (211) definiert, und
wobei die vierte Seite der ersten Berstscheibe (211) eine erste Biegelinie (241) ist,
welche die erste Berstscheibe (211) mit dem zentralen Teil verbindet; und
wobei die zweite Berstscheibe (212) vier Seiten hat, wobei die zweite Sollbruchlinie
(244) ein Schnitt ist, der drei Seiten der zweiten Berstscheibe (212) definiert, und
wobei die vierte Seite der zweiten Berstscheibe (212) eine zweite Biegelinie (243)
ist, welche die zweite Berstscheibe (212) mit dem zentralen Teil verbindet.
7. Druckentlastungsvorrichtung nach Anspruch 6, wobei die erste Biegelinie (241) durch
einen Teilschnitt definiert ist, und wobei die zweite Biegelinie (243) durch einen
Teilschnitt definiert ist.
8. Druckentlastungsvorrichtung nach Anspruch 5,
wobei die erste Sollbruchlinie (242) ein bogenförmiger Schnitt ist, und wobei eine
erste Biegelinie (241) die erste Berstscheibe mit dem zentralen Teil verbindet; und
wobei die zweite Sollbruchlinie (244) ein bogenförmiger Schnitt ist, und wobei eine
zweite Biegelinie (243) die zweite Berstscheibe mit dem zentralen Teil verbindet.
9. Druckentlastungsvorrichtung nach Anspruch 5, ferner umfassend:
ein erstes Gelenkelement, das zwischen der ersten Berstscheibe (211) und dem zentralen
Teil eingreift; und
ein zweites Gelenkelement, das zwischen der zweiten Berstscheibe (212) und dem zentralen
Teil eingreift.
10. Druckentlastungsvorrichtung nach Anspruch 5, ferner umfassend:
ein Kabel (526), das die erste Berstscheibe (511) mit der zweiten Berstscheibe (512)
verbindet;
wobei das Kabel (526) so gestaltet ist, dass es bei Aktivierung der ersten Bertscheibe
(511) eine Zugkraft zwischen der ersten Berstscheibe (511) und der zweiten Berstscheibe
(512) überträgt.
11. Druckentlastungsvorrichtung nach Anspruch 1, umfassend:
eine erste Entlüftung, wobei die erste Entlüftung die erste Scheibe (511) umfasst;
eine zweite Entlüftung, wobei die zweite Entlüftung die zweite Scheibe (512) umfasst;
wobei die erste Scheibe (511) und die zweite Scheibe (512) optional gewölbt sind;
und
ein Verbindungselement (514), das sich zwischen der ersten Scheibe (511) und der zweiten
Scheibe (512) befindet, wobei die erste Scheibe (511) und die zweite Scheibe (512)
so gestaltet sind, dass sie sich im Verhältnis zu dem Verbindungselement (514) drehen;
wobei die erste Scheibe (511) so gestaltet ist, dass sie sich bei Aktivierung der
ersten Entlüftung öffnet;
wobei die zweite Scheibe (512) so gestaltet ist, dass sie sich bei Aktivierung der
zweiten Entlüftung öffnet; und
wobei die erste Scheibe (511) und die zweite Scheibe (512) so gestaltet sind, dass
beim Öffnen wenigstens ihre äußeren Enden eingreifen.
12. Druckentlastungsvorrichtung nach Anspruch 11, ferner umfassend:
ein Kabel (526) mit einem ersten Ende und einem zweiten Ende, wobei das erste Ende
mit der ersten Scheibe (511) verbunden ist, und wobei das zweite Ende mit der zweiten
scheibe (512) verbunden ist, wobei optional wenigstens ein Bremselement mit dem Kabel
(526) verbunden ist; und
wobei optional das Kabel (526) so gestaltet ist, dass es die erste Scheibe (511) und
die zweite Scheibe (512) unter Spannung verbindet.
13. Druckentlastungsvorrichtung nach Anspruch 12, wobei bei Aktivierung der ersten Entlüftung
die erste Scheibe (511) so gestaltet ist, dass sie an dem Kabel (526) zieht und dadurch
die Aktivierung der zweiten Entlüftung auslöst;
wobei das Kabel (526) optional bewirkt, dass die erste Entlüftung und die zweite Entlüftung
im Wesentlichen gleichzeitig aktiviert werden.
14. Druckentlastungsvorrichtung nach Anspruch 11, ferner umfassend:
einen ersten Aktivierungsmechanismus, der so gestaltet ist, dass er einen Druck regelt,
bei dem die erste Entlüftung aktiviert wird; und
einen zweiten Aktivierungsmechanismus, der so gestaltet ist, dass er einen Druck regelt,
bei dem die zweite Entlüftung aktiviert wird.
15. Druckentlastungsvorrichtung nach Anspruch 11, ferner umfassend:
ein erstes Gelenk, das die erste Scheibe (511) drehbar mit dem Verbindungselement
(514) verbindet; und
ein zweites Gelenk, das die zweite Scheibe (512) drehbar mit dem Verbindungselement
(514) verbindet;
wobei das erste Gelenk und das zweite Gelenk optional so gestaltet sind, dass sie
sich verformen und dadurch bei Aktivierung der ersten Entlüftung und der zweiten Entlüftung
kinetische Energie absorbieren.
1. Détendeur de pression, comprenant :
un cadre ayant une partie centrale ;
un premier panneau d'explosion (511) monté dans le cadre, le premier panneau d'explosion
(511) étant conçu pour tourner par rapport à la partie centrale lors de l'ouverture
; et
un second panneau d'explosion (512) monté dans le cadre, le second panneau d'explosion
(512) étant conçu pour tourner par rapport à la partie centrale lors de l'ouverture
;
le premier panneau d'explosion (511) et le second panneau d'explosion (512) étant
conçus pour s'activer et s'ouvrir s'ils subissent un différentiel de pression prédéfini
; et
au moins une partie du premier panneau d'explosion (511) venant en prise avec au moins
une partie du second panneau d'explosion (512) lors de l'activation.
2. Détendeur de pression selon la revendication 1, la partie centrale du cadre définissant
un oeillet ; le dispositif comprenant en outre :
une corde (526) ayant une première extrémité et une seconde extrémité ;
la corde (526) étant passée à travers l'oeillet ;
la première extrémité de la corde (526) étant fixée au premier panneau (511) ; et
la seconde extrémité de la corde (526) étant fixée au second panneau (512).
3. Détendeur de pression selon la revendication 2, la corde (526) étant conçue pour s'assurer
que le premier panneau d'explosion (511) et le second panneau d'explosion (512) s'activent
sensiblement au même moment.
4. Détendeur de pression selon la revendication 2, comprenant en outre :
une première charnière, la première charnière joignant le premier panneau d'explosion
(511) à la partie centrale du cadre ; et
une seconde charnière, la seconde charnière joignant le second panneau d'explosion
(512) à la partie centrale du cadre.
5. Détendeur de pression selon la revendication 1, comprenant :
une feuille ;
la feuille comprenant une première ligne de moindre résistance (242) définissant le
premier panneau d'explosion (211), une seconde ligne de moindre résistance (244) définissant
le second panneau d'explosion (212) ;
la rotation du premier panneau d'explosion (211) créant une première ouverture dans
la feuille ; et
la rotation du second panneau d'explosion (212) créant une seconde ouverture dans
la feuille ; et
au moins une partie du premier panneau d'explosion étant conçue pour entrer en contact
avec au moins une partie du second panneau d'explosion lors de l'activation du premier
panneau d'explosion et du second panneau d'explosion.
6. Détendeur de pression selon la revendication 5 :
le premier panneau d'explosion (211) ayant quatre côtés, la première ligne de moindre
résistance (242) étant une coupe définissant trois côtés du premier panneau d'explosion
(211), et le quatrième côté du premier panneau d'explosion (211) étant une première
ligne de cintrage (241) joignant le premier panneau d'explosion (211) à la partie
centrale ; et
le second panneau d'explosion (212) ayant quatre côtés, la seconde ligne de moindre
résistance (244) étant une coupe définissant trois côtés du second panneau d'explosion
(212), et le quatrième côté du second panneau d'explosion (212) étant une seconde
ligne de cintrage (243) joignant le second panneau d'explosion (212) à la partie centrale.
7. Détendeur de pression selon la revendication 6, la première ligne de cintrage (241)
étant définie par une coupe partielle, et la seconde ligne de cintrage (243) étant
définie par une coupe partielle.
8. Détendeur de pression selon la revendication 5 :
la première ligne de moindre résistance (242) étant une coupe en forme d'arc, et une
première ligne de cintrage (241) joignant le premier panneau d'explosion à la partie
centrale ; et
la seconde ligne de moindre résistance (244) étant une coupe en forme d'arc, et une
seconde ligne de cintrage (243) joignant le second panneau d'explosion à la partie
centrale.
9. Détendeur de pression selon la revendication 5, comprenant en outre :
un premier élément charnière en prise entre le premier panneau d'explosion (211) et
la partie centrale ; et
un second élément charnière en prise entre le second panneau d'explosion (212) et
la partie centrale.
10. Détendeur de pression selon la revendication 5, comprenant en outre :
une corde (526) joignant le premier panneau d'explosion (511) au second panneau d'explosion
(512) ;
la corde (526) étant conçue pour transmettre une force de traction entre le premier
panneau d'explosion (511) et le second panneau d'explosion (512) lors de l'activation
du premier panneau d'explosion (511).
11. Détendeur de pression selon la revendication 1, comprenant :
un premier évent, le premier évent comprenant le premier panneau (511) ;
un second évent, le second évent comprenant le second panneau (512) ;
le premier panneau (511) et le second panneau (512) étant éventuellement bombés ;
et
un élément de raccordement (514) interposé entre le premier panneau (511) et le second
panneau (512), le premier panneau (511) et le second panneau (512) étant conçus pour
tourner par rapport à l'élément de raccordement (514) ;
le premier panneau (511) étant conçu pour s'ouvrir lors de l'activation du premier
évent ;
le second panneau (512) étant conçu pour s'ouvrir lors de l'activation du second évent
; et
le premier panneau (511) et le second panneau (512) étant conçus pour mettre en prise
au moins leurs extrémités externes lors de l'ouverture.
12. Détendeur de pression selon la revendication 11, comprenant en outre :
une corde (526) ayant une première extrémité et une seconde extrémité, la première
extrémité joignant le premier panneau (511) et la seconde extrémité joignant le second
panneau (512), le cas échéant, au moins un élément de freinage étant fixé à la corde
(526) ; et
éventuellement la corde (526) étant conçue pour joindre le premier panneau (511) et
le second panneau (512) en tension.
13. Détendeur de pression selon la revendication 12, lors de l'activation du premier évent,
le premier panneau (511) étant conçu pour tirer sur la corde (526) et ainsi déclencher
l'activation du second évent ;
éventuellement la corde (526) amenant le premier évent et le second évent à s'activer
sensiblement simultanément.
14. Détendeur de pression selon la revendication 11, comprenant en outre :
un premier mécanisme d'activation conçu pour commander une pression à laquelle le
premier évent s'active ; et
un second mécanisme d'activation conçu pour commander une pression à laquelle le second
évent s'active.
15. Détendeur de pression selon la revendication 11, comprenant en outre :
une première charnière joignant de manière rotative le premier panneau (511) à l'élément
de raccordement (514) ; et
une seconde charnière joignant de manière rotative le second panneau (512) à l'élément
de raccordement (514) ;
la première charnière et la seconde charnière étant éventuellement conçues pour se
déformer et ainsi absorber l'énergie cinétique lors de l'activation du premier évent
et du second évent.